Example

DSA not applicable, GPG key checked

The two screenshots are both of the "Mutt" console-based email client.
In one, Mutt is configured to check GPG signatures, and you can see
that the signature on the DSA is preserved within the dsafilter email.
In the other, Mutt is not checking GPG signatures. One example shows
a DSA which is not applicable to the host; the other where the DSA is
applicable (and which binary packages need updating).